import threading,time
def a():
    for i in range(1,11):
        print('+'*20)
        time.sleep(1)
def b():
    for i in range(1,11):
        print('-'*20)
        time.sleep(1)
t1 = threading.Thread(target = a)
t2 = threading.Thread(target = b)
t1.start()
t2.start()
